Three species of birds, two anatids, Dendrocygna bicolor (Vieillot, 1816) (Fulvous Whistling Duck) and Netta peposaca (Vieillot, 1816) (Rosy-billed Pochard), and one phalacrocoracid, Phalacrocorax brasilianus (Gmelin, 1789) (Neotropical Cormorant) were collected from several localities in the Coastal Plain Province and in Lago Guaíba, State of Rio Grande do Sul. The number of birds examined of each host species with the respective values of prevalence and mean intensity of infection of P. ovatus were: 33 D. bicolor, 3%, 1 helminth/host; 20 N. peposaca 15%, 4.3 helminths/host, and 47 P. brasilianus 2.1%, 1 helminth/host. The single specimen collected from the Neotropical cormorants and one of the specimens collected from the rosy-billed pochards, were in the cloaca. The remaining specimens from the rosy-billed pochards and the single specimen from the fulvous whistling ducks were in the bursa of Fabricius. This is the first record of P. ovatus in Neotropical cormorants and rosy-billed pochards. The known geographical distribution of P. ovatus is extended to the southernmost State of Brazil, Rio Grande do Sul.
Anatids; Neotropical cormorants; parasites; Rio Grande do Sul; South America; taxonomy
